Apparatus for and process of refining vegetable and other oils



Mar. 13, 1923.

F. M. TURNER APPARATUS FOR AND PROCESS OF REFINING VEGETABLE AND OTHER OILS- Flled June '7,

SQ EE Patented Mar. 13, lgfid FRANCIS M. TURNER, OF YORK, 1%. Y.

APPARATUS FOR AND PROCESS OF REFINING-VEGETABLE AND OTHER OILS.

applicatlon flled June 7, 1921. Serial No. 475,700.

To all whom it may concern:

Be it known that I, FRANcIs M. TURNER, a citizen of the United States of America, residing at New Yo'rk city, county and State of New York, have invented certain new and useful Improvements in Apparatus for and Processes of Refinin Vegetable and Other Oils, of which the following is a full, clear, and exact description.

This invention relates to improvements in the process of refining oils, more particularly vegetable oils, such as oil from cocoanut, cotton seeds, copra, sesame seeds, or in fact any oils containing fatty acids. Many methods have been devised to obtain edible oils from the above elements with more or less success. So far as I am aware, the methods commonly used are carried out in the presence of air, that is to say, the various steps of the processes are performed in receptacles containing air, and hence'the' oil at all times is under the influence of oxygen and becomes oxidized.

. With my improved process, the various steps are carried out under a high vacuum, that is to say, the receptacles within which the steps are carried out are under a high vacuum during the entire refining process. I am thus able to prevent oxidization, especially during the neutralizing and decolorizing steps. When oils containing fatty acids are neutralized, under present approved methods, an alkali is introduced to neutralize the fatty acids and when the oil is to be used for edible purposes, it is desirable to remove both alkali and neutral ized fatty acids and to this end it is desi.r-'

neutralized acids are precipitated in. insoluble salts and also, by decanting in vacuum,

I remove these salts 1n the absence of moisture laden air. Then during the further treatment, I preventwhatever neutralized acid remains from eontaminating the 'oil,'

which treatment, while especially for the customary steps of bleaching and deodorizmg, se'rves also under my process for the further removal of these neutralized acids. Thus unprecipitated finer salts and incomplete reactions will be recovered during the later treatments while still free from the deleterious contamination. To accomplish this, I carry out the entire refining process under vacuum and preferably a very high vacuum. To this end I have improved the method of separating the fiilter material from the oil which serves also better to remove the residue of these neutralized acids. This improvement is to provide a centrifuge operating inversely to the centrifuges commonly used for separating granules from liquids. In this centrifuge, I drive the granules into pockets upon the exterior walls and direct the liquid internally over the pockets thus retaining in the pockets all granules Whether of reater or less specific gravity than the oil. ven though this and the preceding steps are superior to the previous methods, there still remains volatile fatty acids which would in the air cause saponification and so I carry the vacuum through the volatilizing process and withdraw the volatilized acids by this process. Should saponification take place, it means that the entire batch is ruined for the production of edible tasteless or odorless oils. Theintent of the neutralizing step is to remove all fatty acids and soda-soap, but if there is any moisture present it is almost impossible to remove the soda soap, and furthermore, it takes considerable time to effect the neutralization. To produce a perfect edible oil, it is essential that all of the soap be removed.

In my improved process, the neutralization is carried out in vacuo, thereby avoiding any untoward action of oxygen. By carrying out this step in vacuo, the resultant soda-soap becomes anhydrous and insoluble, rendering the separation thereof from the oil an easy matter.

As the neutralizing step in my improved process is carried out under high vacuum, the danger of formation of emulsions caused by saponification is reduced to a minimum. Furthermore, I 'am able to carry out this step in very much less time than if'the step is carried out in the resence of air, and hence at less expense. efore the neutralizing step takes place, I first compute the amount of fatty acids contained in the oil to be removed. and then combine with the oil the correct amount of caustic soda solu-' tion of a certain specific gravity, the mixture being then placed in a neutral zing tank, to be hereinafter described.

After the neutralizing ste is performed, the treated oil is introduce into a decanting tank. within which the oil and anhydrous soda soap is separated. After the 011 and soda soap have been introduced into the decanter or decanters, the soda soap will settle in the bottom thereof, leaving the oil free.

After the decanting step, I introduce the oil into a tank for the purpose of decolorization. To decolorize the oil, I employ fullers earth, filtchar or a specially prepared carbon (lignite carbon). The decolo'rizing step will also be conducted under high vacuum, which will' prevent oxidization of the oil, which is very important. After the oil is decolorized, it will be passed through filter press, or centrifugal separator, to remove the fullers earth, (or other decolorizing agents), which has been rendered anhydrous, owing to the fact that a high vacuum has been present during the decolorizing step, which eliminates moisture.

After the decolorizing step, the oil will be introduced into a purifying tank or tanks under high vacuum of approximately 29.72 in. when the atmospheric pressure is 29.92 in., and subjected to steam produced from distilled water in a generator which is under vacuum.

From the purifiers the steam and oil are introduced into a separator to separate the oil and steam, the steam being condensed and conveyed to the steam generator, and the oil being conducted into a cooler. The steam flows into a rotaryvacuum condenser, where it becomes condensed and at the same time produces the high vacuum desired.

It will be apparent that the entire process is carried out under a high vacuum, whereby the soda-soap in the oil, which has been neutralized, and the fullers earth or otheragent used in the decolorizing step is rendered anhydrous and hence easily separated from the oil. Furthermore, as the steam usedin the purifying step is generated under vacuum, it Will be produced from water.

which will boil, at about 72 degrees'Fahren heit, as said water will be under a. vacuum of approximately 29.72 in. when the atmospheric pressure is 29.92 inches; hence the temperature of. the steam will be relatively low or in other words, from 113 dc to 140 degrees Fahrenheit; therefore, the delicacy of the flavor of the oil will be retained.

The process as above outlined is applicable topils such as cocoanut, cotton seed, eta, containing fatty acids, which have to be neutralized. With some oils, such as first grade peanut and olive oils, neutralization is not required.

My improved process is intended to refine clarified crude oils, that is to say, oil from which the foots and mucilage have already been removed. This clarified oil contains fatty acids, coloring matter and other substances which must beremoved to render it bland and free from taste, odor, and where desirable, color.

One of the most important features of my invention is that all of the steps are carried out in high vacuo, to revent the resence of oxygen, thus avoiding hydro ysis, and also to render the soda-soaps anhydrous and the decolorizing agents more active. Owing to the fact that the soda soap is rendered anhydrous, it can be more easily separated from the oil, than if it remained in the natural state in the presence of air and moisture; hence, a more perfect oil can be obtained.

In carrying out my improved process, I employ an apparatusillustrated in the accompanying drawings, wherein Fig. 1 illustrates a series of interconnected tanks and vacuum apparatus; and

Fig. 2 illustrates diagrammatically a centrifugal separator.

To carry out my improved process, I employ a tank 1 within which the first step of the' process is carried out, namely, neutralization. The tank 1 contains s'tirrers clarified crude oil is placed in tank 1, mixedv with the proper amount of the neutralizing agent, through the manhole 9 and agitated by the stirrers 2, the shaft 3 being caused to rotate after the tank has been charged. At the proper time a gate valve 10 in the duct 11, will be opened and the treated oil and extracted soda soap will be allowed to flow into the decanting tank 12, and allowed to remain, until the soda soap, which has been rendered anhydrous, during the first step in the operation, settles into the bottom 13 of tank 12. After the soda soaphas settled, the oil in tank 12 will be pumped by means of a centrifugal ump 14, into a tank 6, wherein the oil Wlll be decolorized. After the oil has been delivered to tank 6, the proper amount of fullers earth, filtchar or a specially prepared carbon (lignite carbon) will be introduced into said tank through the manhole 15. After the oil in the tank 6 has received its charge of the decolorizing agent, shaft 3 will be again rotated to cause the stirrers 7. toagitate the mixture. At the proper time the rotation of shaft 3 will be stopped and valve 16 in duct 17 will be opened, allowing the contents of tank 6 to flow into a filter press 18 located within an air-tight chamber 19. After the decolorized oil has been introduced into the filter-press, the plates thereof, indicated by 20, will be forced together by the threaded spindle 21 which carries a hand-wheel 22 (in this instance), but said spindle may be power driven if desirable. After the oil and decolorizing agent have been separated by the press. the oil will flow into a tank 23 thereunder, from which it is taken, by a centrifugal pump 24, and delivered to purifying tanks 25 and 26, through duct 27.

In connection with the tanks 25 and 26, I employ means to introduce steam into the oil within the said tanks. T o introduce steam into the oil, I locate in each tank, a steam spraying device 28 connected by a duct 29 to a generator 30 containing a steam coil 31. Steam will be generated by the coil 31 from distilled water, indicated by 32, and introduced into the oil in tanks 25 and 26, under pressure, through the duct 29 and spraying devices 28. After-the oil has been purified, it Will be drawn off through ducts 33 and 34 and allowed to flow into tanks 35 and 36, containing coils 37 for cold water.

As has been stated, all of the steps above mentioned will be carried out while the tanks are under vacuum, said vacuum being effected preferably by means of a suitable vacuum producing apparatus indicated by 38. The apparatus 38, which acts to effect a vacuum, is of a Well known type operated by a steam jet, which flows into the chamber thereof through a duct 39 and out through an outlet 40.

The steam within the purifiers will be drawn therefrom by the vacuum device 38 into a separator or tank 41. Any oil which may be carried off by the steam will be precipitated when it reaches tank 41, and can be drawn therefrom through the cook 41 in the bottom of the said tank. The pump will be operated by steam introduced thereinto through the duct 39 from a source not shown. The cooling tanks 35 and36 will be connected to the vacuum line by ducts 47 and 48; hence, the oil will be cooled under vacuum. Throughout the entire process, the oil will be out of contact with any air.

In combination with the neutralizing tank 1 and decolorizing tank 6, I prefer to employ heating coils 50 and 51, one in each tank to heat the oil while under treatment in said tanks. The coils 50 and 51 will be preferably heated by steam generated in generating tank 30.

Instead of a filter press, I may employ a centrifugal separator 50 of the Resines type, to separate the oil and decolorizing agent.

Having described my invention, what I claim and desire to secure by Letters Patent is 2- 1. A step in the process of refining crude vegetable and animal oils and fats and of removing anhydrous soap therefrom which consists in subjecting the oil or fat to be neutralized to the action of a'neutralizing agent to remove the free fatty acids therefrom while under vacuum, and removing therefrom all the moisture so that the oil and re sultant soap are anhydrous whereby the soap is insoluble in the said oil or fat.

2. The combination of a tank for neutralizing oils, a settling tank connected there'- with, means to deliver the contents of the neutralizing tank to the settling tank, a decolorizing tank, means to conve oil from the settling tank to the decolorizing tank, a filler press, means to convey the contents of the decolorizing tank to the filler press, a purifying tank, means to convey oil from the filler press to the purifying tank, a coolin tank, meahs to convey oil rom the purifying tank to the cooling tank, and means to place all of said tanks under vacuum.

3. The method of separating soda soap from oils, which consists in mlngling with the oil a sodium neutralizing agent and agitating the same while under high vacuum whereby the soap is rendered anhydrous and then separatingthe soap from the oil.

4:. The process of treating impure edible oils containin free fatty acids consisting in introducing t e oily material into a closed system, producing and continuously main taining a high vacuum throughout the sys tem during all the steps of the process, neutralizing the free fatty acids with the correct mixture of alkali therefor, settling the mixture, decanting the oil from the soap formed, mixin the oil with decolorizing material, and fifiering the mixture, thereby separating the oil.

Signed at New York city, N. Y., this 7th day of June, 1921.

FRANCIS M. TURNER.

Witnesses:

MAURICE BLooK,

EDWARD A. JARVIS. 

